It is well known that in electrical circuitry it is advisable and often necessary to provide a fuse or circuit breaker to protect the circuit from abnormally high current values. In the majority of applications, fuses rather than circuit breakers have been utilized due to their smaller relative size and lower unit cost.
Prior art fuses have typically comprised a thin wire fuse element encased in a glass shell which is connected at both ends thereof to cap terminals. Normally, these fuses are supported by a spring clip receptacle located in a convenient place on the chassis of the device to provide easy access for manual replacement.
Although these prior art fuses have proven useful in their limited prior art applications, they are relatively expensive and subject to misuse and the problem of storing spare fuses.
In particular, with the development and widespread use of printed circuit boards, which are mass produced at a fraction of the cost of hand wired circuitry, the prior art fuse adds substantially to the manufacturing cost of the completed electrical circuitry.
The costs associated with the prior art fuse lie not only in the actual cost of the fuse and holder itself, but primarily in the labor costs incurred in the mounting and wiring of the fuse holder into the circuit. Typically, these fuse holders are mounted at a remote location on the circuit board itself or alternatively on the chassis of the electrical device. In either instance, the mounting of the fuse and holder requires the circuit board or chassis to be provided with a mounting hole or bracket onto which the fuse holder is mounted and subsequently wired. This mounting and wiring is normally facilitated by hand labor and thus substantially increases the production cost.
The use of these prior art fuses has also proven to be unsatisfactory from a manufacturer's viewpoint due to their inability to prevent consumer misuse of the device. Thus, consumers may accidentially or deliberately exchange these fuses with an overrated replacement, thereby causing damage to the electrical device. Similarly, in the case of such use of an overrated fuse, the consumer in an attempt to conceal such misuse may subsequently replace the overrated fuse with a proper fuse and claim a manufacturing defect. In the latter instance, the use of the prior art fuse fails to provide a history to the manufacturer of the deliberate misuse by the consumer.
Additionally, these prior art fuses have also proven deficient from a consumer's standpoint since in order to avoid prolonged nonuse of a particular device caused by fuse burnout, the consumer must store a variety of different rated replacement fuses.